Language Selection

English French German Italian Portuguese Spanish

GPL Enforcement and Violations: Stockfish and More

Filed under
GNU
Legal
  • Our lawsuit against ChessBase

    The Stockfish project strongly believes in free and open-source software and data. Collaboration is what made this engine the strongest chess engine in the world. We license our software using the GNU General Public License, Version 3 (GPL) with the intent to guarantee all chess enthusiasts the freedom to use, share and change all versions of the program.

    Unfortunately, not everybody shares this vision of openness. We have come to realize that ChessBase concealed from their customers Stockfish as the true origin of key parts of their products (see also earlier blog posts by us and the joint Lichess, Leela Chess Zero, and Stockfish teams). Indeed, few customers know they obtained a modified version of Stockfish when they paid for Fat Fritz 2 or Houdini 6 - both Stockfish derivatives - and they thus have good reason to be upset. ChessBase repeatedly violated central obligations of the GPL, which ensures that the user of the software is informed of their rights. These rights are explicit in the license and include access to the corresponding sources, and the right to reproduce, modify and distribute GPLed programs royalty-free.

  • Stockfish sues ChessBase

    The Stockfish project, which distributes a chess engine under GPLv3, has announced the filing of a GPL-enforcement lawsuit against ChessBase, which has been (and evidently still is) distributing proprietary versions of the Stockfish code.

  • Are you compliant with open-source license obligations?

    A short answer is no. Your piece of software will not be open-source if it doesn’t have an open-source license. Under copyright law, such software is copyrighted by default, with all the restrictions that this implies.

    If you want anyone to use your code freely, you should ensure certain liberties commonly called “the four freedoms“. They say that OS software may be used, studied, modified, and distributed freely, as long as the license is respected.

    For the first three, there are no conditions of any kind; you are free to use, study, and modify the code for any purpose. If you move beyond that and decide to distribute your modified version (or the original), this is when open-source license compliance starts.

    Missing license texts are the number one cause of license infringement cases, which, as we’ve seen above, can lead to the loss of ownership rights and enforcement actions such as an interim injunction.

Stockfish Contributors Sue ChessBase for GPL Violations

  • Stockfish Contributors Sue ChessBase for GPL Violations

    A legal reckoning is brewing in the world of open source chess engines. Stockfish, a GPL-licensed chess engine widely recognized as one of the strongest in the world, has filed a lawsuit against ChessBase. The German-based company makes and sells chess software that relies heavily on the Stockfish engine, maintains a prominent chess news site, and runs a chess server for online games.

    [...]

    “This chess engine is a Stockfish derivative, with a few lines of code modification (engine name, authors list and a few parameters), and a new set of NNUE net weights considered proprietary,” current Stockfish maintainer Joost VandeVondele said. “ChessBase’s communication on Fat Fritz 2, claiming originality where there is none, has shocked our community. Furthermore, the engine Fat Fritz 2 fails to convince on independent rating lists, casting doubt on the usefulness of those modifications. Indeed, we feel that customers buying Fat Fritz 2 get very little added value for money. Claims to the contrary appear misleading.”

Stockfish Developers Sue Chessbase Claiming Copyright Violation

  • Stockfish Developers Sue Chessbase Claiming Copyright Violation

    The Stockfish team has filed a lawsuit against Chessbase, claiming that the German chess software company is selling their software without having the license to do so. The lawsuit, filed in a German court, was announced last Tuesday in a blog on the Stockfish website.

    The Stockfish team argues that Chessbase has "concealed from their customers Stockfish as the true origin of key parts of their products," namely Fat Fritz 2 and Houdini 6. According to the Stockfish team, Chessbase has "repeatedly violated central obligations of the GPL," which refers to informing software users of their rights. "These rights are explicit in the license and include access to the corresponding sources, and the right to reproduce, modify and distribute GPLed programs royalty-free," the Stockfish team writes.

  • GitHub Copilot sparks debates around open-source licenses

    A few weeks ago GitHub released its Copilot solution, which uses AI to suggest code to developers. Developers can write a comment in their code and Copilot will automatically write the code it thinks is appropriate. It’s an impressive example of the power of AI, but has many developers and members of the open-source community upset and worrying over what it means for the future of open source.

Comment viewing options

Select your preferred way to display the comments and click "Save settings" to activate your changes.

More in Tux Machines

Games: Proton, Neptune 15 v2, and VR

  • What is Proton? | TechRadar

    You may have seen lots of mentions of Proton with the upcoming launch of the Steam Deck handheld game console, but what is it, and how does it work? Proton is a piece of software created by Valve and CodeWeavers that acts as a compatibility layer that allows games designed for the Windows 10 and Windows 11 operating systems to run in Linux with a minimal impact on performance. Proton is based on the existing WINE tool, which allowed Windows applications to run in Linux, with Valve and CodeWeavers taking the tech and using it to specifically run games. This is incredibly useful, as the vast majority of games are coded for Windows, due to the sheer popularity of Microsoft’s operating system. Linux, a free and open-source operating system, is relatively niche, which meant that many game developers couldn’t – or wouldn’t – spend resources on making a port of their games to run natively on Linux.

  • Neptune 15 v2 from Juno is a Linux Gaming Laptop with 240 Hz Display

    The Neptune 15″ V2 from Juno Computers is powered by Intel’s 10th-gen Comet Lake chipsets, and can be configured with up to 64GB of RAM. Nowadays, it is a little difficult to choose a perfect Linux gaming laptop, but it is not impossible to get it. As well as, these laptops are prepaid with full advantages like an additional graphic card with a brilliant CPU. In fact, some of the best Linux gaming laptops offer up the same durability and premium design as their Windows counterparts. They’ll also cost less since there’s no Windows license included with the laptop.

  • Humble has a nice looking VR bundle if you need some more games | GamingOnLinux

    Do you have a VR kit that's begging to be played? Check out the Fall VR Emporium Bundle over on Humble Bundle. Sadly, there's not many native / supported Linux VR games and so you're going to need Steam Play Proton to enjoy this set of games.

Plasma 5.23 Anniversary Edition Beta available for testing

Are you using Kubuntu 21.04 Hirsute Hippo, our current Stable release? Or are you already running our development builds of the upcoming 21.10 Impish Indri? We currently have Plasma 5.22.90 (Plasma 5.23 Anniversary Edition Beta) available in our Beta PPA for Kubuntu 21.04, and 21.10 development series. However this is a beta release, and we should re-iterate the disclaimer from the upstream release announcement... Read more Also: Using KNotifications in QML

Top 20 Open-source solutions for Photographers

In today world, editing photos is a critical component in the overall photography process, and it was taken a new level of importance. As demand continues to rise and the market is filled with plenty of capable options, we will suggest top 20 apps to enhance your photography workflow. We take many free high-quality photo editors without having to pay for an expensive program to edit your image like a pro. Read more

LibreOffice 8.0 New tabbed interface layout available

Muttakin Rizal ( Rizal Muttaqin ), one of the designers LibreOffice office suite, has published in his blog, the user interface possible development plan LibreOffice 8.0. The most notable innovation is the built-in support for tabs, through which you can quickly switch between different documents, similar to how switching between sites is carried out in modern browsers. If necessary, each tab can be unpinned in the form of a separate window, or vice versa, convert the window into a tab. It is also possible to collapse all tabs into a drop-down list accessible by pressing the “^” button. The header also shows a LibreOffice button to launch the initial interface, which was previously shown when starting or closing all documents, to open a file, visually evaluate recently opened documents, or create a new document based on a template. Read more